domr

I'm addressing a boost leak on a 2008 S65 and I think it's the y-pipe. I've tried a variety of hose clamps but still get leaks near the intercooler interfaces. I'm considering buying a new y-pipe to see if it cures my issue. The part number for my model year is 2750981516. The newer engines use 2790980016. Intercooler and throttle body part numbers between the M275 and M279 are the same, so it seems the same y-pipe could be used. I'd prefer to use the latest version if possible in case there's an improvement. Does anyone have experience with this? Or will I have to be the guinea pig? Other cures for sealing this y-pipe? Thanks.

DaleB

Call me crazy, but I'd try some self-fusing silicone tape. I picked some up at Oshkosh a few years ago. Works well, stands up to heat, and if you do it right (stretch and wrap) it sticks to itself quite well.

domr

Thanks for the idea. I tried your suggestion but couldn't get a good seal. I did get a loud whistle under boost which was entertaining for a day.

I ended up ordering the M279 version of this part. The top surface is flat vs round like the M275 version. The space between left and right intercoolers is wider on the M279 version. Despite these differences it fit fine. The construction of the part looks the same, so probably no benefit to using the newer part.

JJKCMO

I went to change my oil and noticed my y-pipe was disconnected at the throttle body just a bit. I've removed it and found it is split a bit. Do I need to disconnect the intercoolers to install a new one - it doesn't appear there is a way to fit the connections to both intercoolers and the throttle body without removing at least one of the intercoolers.

domr

Yes, just move the intercoolers out of the way enough to get the new one on. Don't disconnect the coolant lines.

JJKCMO

Thank you.

Still waiting on my new part to install, but this will help.

DaleB

Did you have any problems installing it? Mine is toast, I need to order another one.

domr

No problems installing it, but I didn’t see any reason to use the 279 version over the 275 version.

DaleB

The newer part is a buck cheaper.